/*
 * Copyright 2002-2011 Guillaume Cottenceau and contributors.
 *
 * This software may be freely redistributed under the terms
 * of the X11 license.
 *
 */

#include <unistd.h>
#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include <stdarg.h>
#include <iostream>
#include <stdint.h>

#include "matcher.h"

#define PNG_DEBUG 3
#include <png.h>

void abort_(const char * s, ...)
{
        va_list args;
        va_start(args, s);
        vfprintf(stderr, s, args);
        fprintf(stderr, "\n");
        va_end(args);
        abort();
}

int x, y;

int width, height, rowbytes;
png_byte color_type;
png_byte bit_depth;

png_structp png_ptr;
png_infop info_ptr;
int number_of_passes;
png_bytep * row_pointers;

void read_png_file(char* file_name)
{
        unsigned char header[8];    // 8 is the maximum size that can be checked

        /* open file and test for it being a png */
        FILE *fp = fopen(file_name, "rb");
        if (!fp)
                abort_("[read_png_file] File %s could not be opened for reading", file_name);
        fread(header, 1, 8, fp);
        if (png_sig_cmp(header, 0, 8))
                abort_("[read_png_file] File %s is not recognized as a PNG file", file_name);


        /* initialize stuff */
        png_ptr = png_create_read_struct(PNG_LIBPNG_VER_STRING, NULL, NULL, NULL);

        if (!png_ptr)
                abort_("[read_png_file] png_create_read_struct failed");

        info_ptr = png_create_info_struct(png_ptr);
        if (!info_ptr)
                abort_("[read_png_file] png_create_info_struct failed");

        if (setjmp(png_jmpbuf(png_ptr)))
                abort_("[read_png_file] Error during init_io");

        png_init_io(png_ptr, fp);
        png_set_sig_bytes(png_ptr, 8);

        png_read_info(png_ptr, info_ptr);

        width = png_get_image_width(png_ptr, info_ptr);
        height = png_get_image_height(png_ptr, info_ptr);
        color_type = png_get_color_type(png_ptr, info_ptr);
        bit_depth = png_get_bit_depth(png_ptr, info_ptr);

        number_of_passes = png_set_interlace_handling(png_ptr);
        png_read_update_info(png_ptr, info_ptr);


        /* read file */
        if (setjmp(png_jmpbuf(png_ptr)))
                abort_("[read_png_file] Error during read_image");

        row_pointers = (png_bytep*) malloc(sizeof(png_bytep) * height);

        if (bit_depth == 16)
                rowbytes = width*8;
        else
                rowbytes = width*4;

        for (y=0; y<height; y++)
                row_pointers[y] = (png_byte*) malloc(rowbytes);

        png_read_image(png_ptr, row_pointers);

        fclose(fp);
}

void readImage(uint8_t *I) {
    int x, y, n=0;
    unsigned char * ptr;
    unsigned char * row;
    for (y = 0; y < height; y++) {
        row = row_pointers[y];
        for (x = 0; x < width; x++, n++) {
            ptr = &(row[x*3]);
            I[n] = (int16_t)(ptr[0] + ptr[1] + ptr[2]);
        }
    }
}


void write_png_file(char* file_name)
{
        /* create file */
        FILE *fp = fopen(file_name, "wb");
        if (!fp)
                abort_("[write_png_file] File %s could not be opened for writing", file_name);


        /* initialize stuff */
        png_ptr = png_create_write_struct(PNG_LIBPNG_VER_STRING, NULL, NULL, NULL);

        if (!png_ptr)
                abort_("[write_png_file] png_create_write_struct failed");

        info_ptr = png_create_info_struct(png_ptr);
        if (!info_ptr)
                abort_("[write_png_file] png_create_info_struct failed");

        if (setjmp(png_jmpbuf(png_ptr)))
                abort_("[write_png_file] Error during init_io");

        png_init_io(png_ptr, fp);


        /* write header */
        if (setjmp(png_jmpbuf(png_ptr)))
                abort_("[write_png_file] Error during writing header");

        png_set_IHDR(png_ptr, info_ptr, width, height,
                     8, 6, PNG_INTERLACE_NONE,
                     PNG_COMPRESSION_TYPE_BASE, PNG_FILTER_TYPE_BASE);

        png_write_info(png_ptr, info_ptr);


        /* write bytes */
        if (setjmp(png_jmpbuf(png_ptr)))
                abort_("[write_png_file] Error during writing bytes");

        png_write_image(png_ptr, row_pointers);


        /* end write */
        if (setjmp(png_jmpbuf(png_ptr)))
                abort_("[write_png_file] Error during end of write");

        png_write_end(png_ptr, NULL);

        /* cleanup heap allocation */
        for (y=0; y<height; y++)
                free(row_pointers[y]);
        free(row_pointers);

        fclose(fp);
}


void process_file(void)
{
        /* Expand any grayscale, RGB, or palette images to RGBA */
        png_set_expand(png_ptr);

        /* Reduce any 16-bits-per-sample images to 8-bits-per-sample */
        png_set_strip_16(png_ptr);

        for (y=0; y<height; y++) {
            png_byte* row = row_pointers[y];
                for (x=0; x<width; x++) {
                        png_byte* ptr = &(row[x*4]);
                        //printf("Pixel at position [ %d - %d ] has RGBA values: %d - %d - %d - %d\n",
        //                               x, y, ptr[0], ptr[1], ptr[2], ptr[3]);

                        /* perform whatever modifications needed, for example to set red value to 0 and green value to the blue one:
                           ptr[0] = 0;
                           ptr[1] = ptr[2]; */
                }
        }
}

void clearPtrs() {
    int py;

    for (py=0; py<height; py++)
        free(row_pointers[py]);
    free(row_pointers);
}

int main()
{
        read_png_file("/home/robot/shmelya/svn/eurasiacb/projects/cpp/csharpblessyou/I1_000000.png");
        uint8_t* imageOf1 = new uint8_t[width*height];
        readImage(imageOf1);
        clearPtrs();

        read_png_file("/home/robot/shmelya/svn/eurasiacb/projects/cpp/csharpblessyou/I1_000001.png");
        uint8_t* imageOf2 = new uint8_t[width*height];
        readImage(imageOf2);
        clearPtrs();

        Matcher mmm;
        mmm.pushBack(imageOf1, width, height, width, true);
        //mmm.pushBack(imageOf2, width, height, width, false);

        return 1;
}
